package org.appenders.log4j2.elasticsearch.metrics;

/*-
 * #%L
 * log4j2-elasticsearch
 * %%
 * Copyright (C) 2022 Rafal Foltynski
 * %%
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 * 
 *      http://www.apache.org/licenses/LICENSE-2.0
 * 
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 * #L%
 */

/**
 * Classes implementing this interface are expected to register all their metrics on {@link #register(MetricsRegistry)} call
 */
public interface Measured {

    Measured NOOP = registry -> {};

    static Measured of(Object obj) {
        return obj instanceof Measured ? (Measured) obj : NOOP;
    }

    /**
     * SHOULD register all metrics provided by itself and it's {@link Measured} delegates with given {@link MetricsRegistry}
     *
     * @param registry metric registry
     */
    void register(final MetricsRegistry registry);

    /**
     * SHOULD deregister all metrics provided by itself and it's {@link Measured} delegates
     */
    default void deregister() {
        // noop
    }

    /**
     * MAY register all metrics provided by given {@link Measured} instance at available {@link MetricsRegistry}
     *
     * @param measured external metric provider
     */
    default void register(final Measured measured) {
        // noop
    }

}
